Very Long Mash

[Sheldon]

So I was going to brew a Wee Heavy this morning. Got the Mash water heated and mashed in the grains when I get a call from my son that I need to take him to the ER because his back is really hurting and he can't get a dr appointment today. So my grains will be bathing for at least 8 hours before I hope to be back some time this evening to continue with the brew. I won't be reading responses till I get back, but since this is the first time I've been interupted in the midst of a brewing session, I am looking for any guidance or tips on how to proceed (if different than normal) when I pick up my process tonite.

Thanks,

Sheldon

 

[hibbleton]

I would think that you should expect high attenuation due to a very long mash and low temperatures (unless somehow your mash tun can maintain a temp that long). I'd maybe add some maltodextrin or other unfermentables to boost the body of the beer.

 

[permo]

I overnight mash almost exclusively now, your conversion largely takes place in the first 40 minutes and the temperature at which this occurs will determine the amount of dextrines in your wort. After conversion is completed your wort is just sitting there waiting for you.

the only difference that I notice is about %5 increase in efficiency when I overnight mash, I am assuming that this is due to the long soak or somehow softening the grain more and making it easier to sparge the sugars off.....not sure about that but I like it.

So long as you keep your mash above 140 you have nothing to worry about.

 

[jaginger]

2 questions for you permo:

1) Why do you mash overnight -- is it solely for the 5% bump or some other reason?

2) Why is 140 the magic temp?


I ask b/c this might work great for me. It's always tough to find time to brew with the family (and 2nd daughter on the way.)

I could get a mash started late at night, then get up early (since I'll be doing that anyway!) to boil.

 

[JuanMoore]

Can't speak for permo, but most who mash overnight do it for time/schedule reasons. You should expect slightly higher attenuation and efficiency, both of which can easily be accounted for by adjusting your recipes and/or mash temps slightly.

The enzymes that we use to convert the starches into sugars aren't active below 140F. Mashing lower would lead to a lack of conversion, as would mashing too hot. The two main active enzymes are alpha amylase which produces more complex sugars, and beta amylase which creates simpler sugars. By mashing at the lower end of the range (low 140's) the beta amylase is more active and the resulting wort is highly fermentable for a dry beer. By mashing at the warmer end of the range (160's) the alpha amylase is more active and the resulting wort is less fermentable resulting in a sweeter and fuller bodied beer. Most beers are mashed between 150F and 160F for a good balance.

 

[permo]

When overnight mashing I try to make sure I insulate my mash tun well enough not to fall below 140 because I want no chance of lacto or any other microbe souring my mash. I researched and the real magic number is 130, but I shoot for 140. Like I said above, the temp that the conversion happens at determines the dextrine content and fermentability. So long mashes do not make a more fermentable wort.

I have two jobs, a 10 month old gilr and a 3 year old girl. Overnight mashing allows me to brew while they are fast asleep, and as a benefit I get better efficiency. It also seems like my beers have more "spunk". I think the long soak lets the specialty grains really flavor the wort.

http://www.brewboard.com/index.php?showtopic=30815

I recently did an overnight mash with a 2 oz mash hop, so I have no doubt that will yield a nice hop flavor and aroma to the beer as well.

 

[rjwhite41]

The real problem with getting below 140 is the wort can sour as stated above. Once all the sugars are converted it really doesn't matter what your temperature is other than that and as someone else stated that happens in the first hour generally anyway. You will see higher efficiency but I have not noticed any higher attenuation from a longer mash (unless done at a lower temperature of course).

 

[Sheldon]

Well, I got back and finished brewing just a short time ago. 5.25 gal at 1.080. Time will tell. Thanks for the input.

 

[npauley88]

let us know how it ferments! I'm interested in this long/over night mash myself.